Telomere reduction in scleroderma patients: a possible cause for chromosomal instability.

We have hypothesized that the chromosomal instability observed in scleroderma patients and their family members may result from the loss of long stretches of the telomeric repeat which is found at the ends of all linear chromosomes. We examined the telomere lengths in scleroderma (SSc) patients (n = 43), their family members (n = 182) and in age-matched controls (n = 96) using restriction fragment length polymorphism (RFLP) and chemiluminescent labelled probes. The average loss of telomeric DNA in SSc patients and family members was found to be 3 kb when compared to the controls. This loss was not related to age or the duration of the disease. These results may reflect a genetic predisposition for chromosomal instability in these families, or exposure to a common environmental agent. A wide variety of common environmental agents are known to produce chromosomal aberrations: these include fungicides, pesticides, air pollutants and drugs. Scleroderma-like syndromes may be induced by some of these agents.